Painting machine



Oct. 25, 1960 G. DYNIA PAINTING MACHINE 4 Sheets-Sheet 1 Original Filed Nov. 26, 1956 INVENTOR. GEDFQGE DYNIA BY J 8/5 I ATTOW Oct. 25, 1960 G. DYNIA PAINTING MACHINE 4 Sheets-Sheet 2 Original Filed Nov. 26, 1956 'IIIIIIIIl/IIIIIIIIIIIII INVENTOR. G E ORGE DY N l A W ATTOR/VZY Oct. 25, 1960 G. DYNIA PAINTING momma:

4 Sheets-Sheet 3 Original Filed Nov. 26, 1956 INVENTbR, GEORGE DYNIA Oct, 25, 1960 a. DYNIA 2,957,448

PAINTING MACHINE Original Filed Nov. 26, 1956 4 Sheets-Sheet 4 INVENTOR. GEORGE DYNIA ATTOP/VEY United States Patent O PAINTING MACHINE George Dynia, 153-23 77th Ave.,Flushing, N.Y.

Original application Nov. 26, 1956, Ser. No. 624,352,

now Patent No. 2,892,439, dated June 30, 1959. .Divided and this application May 12,1959, Ser. No.

6 Claims. (Cl. 118-4) This invention relates to a machine adapted to effect automatically the painting of a ceiling or wall surface of a room or other enclosure. This application is a division of my ccpending application Serial Number 624,352, filed November 26, 1956, now Patent No.

use of a wheeled support, which in one form of the invention is self-propelled, and includes a motion-translating linkage to an oscillating, automatically extensible arm on the upper end of which is provided a roller-type applicator, so that on movement of the support along a floor surface, the arm is continuously oscillated with the applicator coating progressively exposed surfaces during its back and forth motion across said surfaces. Means is provided in association with the applicator adapted to trip an electrical switch responsive to striking an obstruction on the ceiling being coated, which obstruction might be a depending light fixture, etc., a wall, or the like. Immediate reversal of the direction of movement of the applicator is effected by the tripped switch, causing the apparatus to move away from said obstruction and, in efiect, paint around the same.

The support carries a reservoir for the paint or other coating material, in which the material is maintained under pressure to continuously feed the applicator, and also carried upon the support is hydraulic means for automatically maintaining the oscillating arm in an extended condition, so designed as to cause the painting head .to

travel back and forth in a plane just below and paralleling that of the ceiling despite the oscillatory motion of the arm, which would ordinarily tend to cause said painting head to travel in an arcuate path about the axis on which the extensible arm is pivoted.

Among important objects of the invention are the fol- .lowing:

To provide a wholly automatic, self-propelled painting or surface-coating machine;

To so design said machine as to cause the same to coat a large surface area in a minimum amount of time,

the invention thus being well adapted for use in coating large, flat expanses of wall and ceiling area, such as those found in auditoriums, gymnasiums, etc.;

To so design the machine as to cause the same to automatically reverse the direction of movement of the painting head on arrival of the painting head at any obstruction;

To form a painting machine of the character described that will be relatively simple in construction, considering the substantial benefits to be derived from the use thereof;

2,957,448 patented Oct. 25, 19 0 lce movement of the painting head; and

To provide a painting machine of the character described that canbe readily transported from place to place, will be compact, substantially trouble-free in operation, and adapted by a novel assemblage and interrelationship of said components to efiiciently discharge its intended functions.

For furthercomprehension of the invention, and of the objects and advantages thereof, reference will be had to the following description and accompanying drawings, and to the appended claims in which the various novel features of the invention are more particularly set forth.

In the accompanying drawings forming a material part of this discolsure:

Fig. 1 is a transverse sectional view through the apparatus substantially on line 1-1 of Fig. 2, viewing the apparatus at its head, end, the oscillating arm and supported painting head being shown in full, chain-dotted, and dash-dotted positions at various locations to which it is moved.

Fig. 2 is a longitudinal sectional view substantially on line 2-2 of Fig. 1, through the apparatus.

Fig. 3 is an enlarged sectionalview substantially on line 3-3 of Fig.2, showing the motion-translating asarm assembly, substantially on line 6-6 of Fig. 5, the

scale being further enlarged.

Fig. 7 is an enlarged perspective view of head.

Fig. 8 is a transverse section through the painting head substantially on line 8-8 of Fig. 7, the scale being enlarged above that of Fig. 7, the switch means being shown in difierent positions to which it is movable in full and dotted lines respectively.

Fig. 9 is a detail section, enlarged above the scale of Fig. 7, substantially on line 9-9 of Fig. 7, showing the connection of the feeler frame to the switch support plate.

Fig. 10 is an enlarged sectional view substantially on line 10-10 of Fig. 2, showing the pressure fluid reservo1r.

Fig. 11 is diagram showing the path of the painting head.

Fig. 12 is a somewhat diagrammatic view showing a modified motion-translating driving connection for efiecting oscillating movement of the painting arm assembly.

Fig. 13 is a sectional view substantially on line 13-13 of Fig. 12.

The first form of the invention has been illustrated in Figs. 1-l0, inclusive. It includes an upwardly opening shell or housing generally designated 10 which is approximately rectangular in shape, is fully open at its top, and is fully closed at its sides, bottom, front, and rear. The housing can be of various forms, that shown being merely one of many shapes that might be employed.

The hosing is rollably supported, including transversely extending, horizontal, front and rear axles 12, 14, to which are fixedly secured front-and rear wheels 16, 18, respecthe painting ing of any: ofva.rious conventional. types, down the speed of:-an axle-orshaft24 pro ecting at oppothe speed with which tively. On the bottom of the housing, there is mounted an electric motor 20, of the gear head type, having a forwardly projecting gear box 22 containing reduction geardesigned to-step site directionfrom the gear box, to aselected extent. At

this-point, it will be understood that therelative speeds -of the motor shaft, the driven shaft 24, the wheel axles,

and of the oscillating-arm assembly, may bevaried within the scope of the appended claims-without departure. from the spirit oftheinvention as claimed. One can so establish the speed through the usevof suitable reductiongearing, and relative sizes of gears, etc., as to cause the housing to move forwardly at a predetermined speed bearing a timed relation to the speed of oscillating motionof the arm assembly. Hence, it would appearthat a further discussion ofthese yarious'relative speeds is immaterial,

it being mainly important that the.forward. movementvof the housing and the speed of movement of the painting head be timed one relative to the other in a manner to assure that the painting head will properly coat the surface to which paint is being applied, without applying either an excessive amount ofpaint or, on the other hand, an excessively small amount of paint.

The housing is adapted to be self-propelled, in 'a direction toward the left in Fig. .2, and to this end there is secured to the shaft 24 that projects from the gear head 22 a gear 26 (see Fig. 2) in mesh with a gear 28 secured to the shaft 12.

Mounted within and projecting upwardly from the housing at the head end thereof is a motion-translating assembly generally designated 30. Said assembly translates rotary motion of one shaft to oscillating motionof apaint head-supporting arm assembly to bedescribed hereinafter. It is believed that any of various motion-translating linkages that will translate motion in this manner may be employed. It is mainly important that the previously mentioned timed relationship of thepain'ting head movement to the speed movement of the rollable support over a floor surface be retained, and it' is also important that the paintinghead moves over the ceiling C being painted he maintained at a'substantially uniform rate to assure correspondingly uniform distribution of the coating material over the ceiling surface. It is also important that the assembly 30 be so driven from shaft 24 that a reversal of the direction of drive thereof can be readily effected.

The motion-translating assembly shown in Figs. 3 and 4 is, accordingly, provided merely by way of example of one that could be employed to advantage. It includes a rectangular, forwardly opening casing 32 closed' at its front by a removable cover plate 34 and supported upon and secured to transversely extending,.confronting angle bars 36, 36 secured fixedly at their ends to the respective side walls of the housing 10.

Referring to Fig. 1, an electrically actuated reversing clutch 37 drivingly connects shaft 24 to a shaft 39, in a manner that will permit shaft 39 to rotate either in the same direction as or oppositely to the shaft 24. Secured to the shaft 39 is a pulley 38 about which is trained a belt 40 and trained also about a driven pulley 42 secured to a shaft 44 journalled at its ends in the side walls of casing 32 (see Figs. 3 and 4). Secured to the shaft 44 is a worm gear 46 meshing with and driving a helical gear 48 secured to a shaft 50 journalled in the cover plate 34 and in the back wall of casing 32 (see Fig. 4) at right angles to shaft 44. Secured to shaft 50 is a pinion 52 mesh-ing with a large gear wheel 54 rotating upon a stub shaft or arbor 56 that projects forwardly a short distance from the back wall of the casing 32, the front end of the stub shaft being flush with the front surface of the gear wheel. 7

Secured to and depending from the-top wall of casing 32is a bearing sleeve-58: extending in aifore-and-aft. direction. .Journalled inthabearingslceveis a spindle Gib-held against axial movement relative to the sleeve by set collars.

tudinally slotted arm 62 projecting radially from shaft 60. Projecting forwardly from the marginal portion of gear wheel 54 is a lug 64 slidably engaging in the slot of arm member 62 (see Fig. 3). Thus, on rotation of gear wheel 54 the pin 64 will travel in a circular path, and will, accordingly, cause arm 62 to oscillate between opposite extreme positions which in a preferred embodiment may be angularly spacedsixty degrees apart.

This causes the sp' d1e..60 to rock about its long axis in opposite .directionsatapredetennined rate of speed and tbrougha predeterminedangular distance.

The spindle 60 projects at its front end through a slot 64 formed in thecover plate 34, and the forwardly pro jecting end is welded or otherwise fixedly secured to the lower end of an elongated, telescopic, paint head supporting armwassembly generally designated at 66.

' The particular formation of arm assembly 66 is shown to its best advantagein Fig. 5. Said assembly includes a cylindrical base section comprising a tubular member 70 threaded at' its opposite ends to receive upper and lower end caps 72,74. End cap 74 has an inlet fitting 75 to which is connectible a flexible hose 76 through which fluid under pressure is supplied to the base cylinder.

Telescoping in the base cylinder is an intermediate cylinder 78, sliding. in an opening formed in upper end cap 72. Rotation of intermediate cylinder 78 relative to base cylinder 70 should be prevented and as one means for accomplishing this, there is illustrated a longitudinal key or. rib'80 formed upon the outer surface of cylinder 78 (see Figs. 5 and '6) and sliding into a complementarily formed recess provided in end cap 72 in communication with the center opening of the end cap.

The. inner end of intermediate cylinder 78 is outwardly flanged at'82 to provide a piston havingwiping contact with .the wall of base cylinder 70 and to prevent leakage element of corresponding cross section, this arrange- 'ment preventing axial rotation of the shaft element relative to the intermediate cylinder. Shaft element 90 at its inner end has apiston-defining flange 92 supporting seal rings 93.

The arrangement illustrated in Fig. 5 is such that on pressure fluid being supplied to base cylinder 70, the intermediate cylinder78 and the shaft element will.be automatically extended by pressure exerted against the pistons 82, 92, respectively.

At its outer or upper end, shaft element 90 has an annular enlargement 94 in the center opening of which there is welded one end of an elongated, horizontal tube 96 extendedperpcndicularly to the length of shaft element 90 and formed at one end with an inlet fitting to which is connectible a flexible hose 98 through which paint or other coating material is supplied to the interior of the tube.

The tube constitutes part of a painting head generally designated at 68, adapted to traverse the ceiling C on oscillation of arm assembly 66.

At its other end, the tube is closed by a removable plug 100, facilitating cleaning of the interior of the painting head.

Rotating on the tube 96 is a painting head cylinder 102, about which is snugly fitted a sleeve 104 of a porous, nappy material such as those commonly used on painting rollers.

Within the cylinder 102, tube 96 is formed with longitudinally extending, circumferentially spaced rows of apertures 108, through which the paint is forced into the cylinder 102, and correspondingly longitudinally extending, circumferentially spaced ports are formedin the 'wall of cylinder 102, so that the paint is forced into 'the porous material of the sleeve 104, to be uniformly dispersed through the sleeve and coated upon the surface of ceiling C on traverse of the ceiling by the painting head roller.

The construction so far illustrated and described is such (see Fig. 1) that the arm assembly 66 is automatically extended to its maximum extent, that is, said assembly is extended as far as it is permitted by the particular position which it assumes during its'oscillatory motion, in a manner to maintain the surface of sleeve 164 in engagement with the ceiling In other words, the painting head travels along the ceiling surface, being maintained wholly in a plane paralleling that of the ceiling, despite the oscillatory motion of the arm assembly. Considering the arm assembly as moving from its full to its chain-dotted position of Fig. 1, it will be seen that the arm assembly is automatically shortened, with the arm assembly then automatically lengthening as it moves from its chaindotted to its dash-dotted position of Fig. 1. A more detailed discussion of the manner in which this operational characteristic obtains will be provided hereinafter.

Carried by the painting head is a switch and switch actuating mechanism shown to its best advantage in Figs. '7 'and 8. The switch actuating mechanism includes a rectangular, thin wire guard 112, the longitudinal portions of .which parallel the axis of the painting roller and are disposed at opposite sides of said axis. Said longitudinal portions are formed with uniformlyspaced, laterally outwardly projecting, feeling tips 114 which may be convemently formed by folding the material of the longitudinal portions of the guard upon itself at selected locai f tions as shown in Fig. 7. The feeler tips have their outer ends projecting well beyond the respective sides of the painting roller, so that'they will engage any obstruction "depending from the ceiling, such as a light fixture, and

so that they will, further, engage a vertical wall surface or the like before the painting head can strike the ob struction.

At its inner end, the guard is provided with small rollers 116, which roll upon the surface of ceiling C. As will be noted, the rollers are disposed beyond one end of the painting roller, and are so located as to roll upon that of the ceiling which has not yet been coated.

Bearings for the guide rollers 116 may be formed out of the material of the adjacent end of the guard. The pur- .',pose of the guide rollers 116 is to maintain the guard 112 in a horizontal plane paralleling and closelyspaced from that of the ceiling C as shown to best advantage in Figs. 1, 2 and 8.

Midway between the guide rollers 116, the material of the wire guard 112 is extended longitudinally beyond the adjacent end of the guard in the form of a support arm 118 of the guard, having an inverted L-shape. At the lower end of the vertical leg of support arm 118 said arm is formed with a loop loosely receiving a screw 122 threaded into the rounded upper end of a flat switch support plate 120 disposed in a vertical plane. This is shown to best advantage in Figs. 8 and 9.

Formed in the plate 120 is a longitudinalslot 123 having rounded ends, and receiving the tube 96 so that the plate is rotatably mounted upon tube 96, and further is adapted to'slide in a direction radially of said tube. To hold the plate against axial'movement along the length of the tube 96 a stop screw or lug 125 may be threaded into the tube as shown in Figs. 7 and 8, bearing against one face of the plate, the other face of the plate bearing against the annular enlargement 94 of shaft element 90.

' The plate normally depends vertically from tube 96 as shown in Fig. 8 in full lines, with the tube engaging the "rounded upper end of slot 123. To insure that the plate will so depend under normal conditions, the plate may as shown he provided at its lower end with a transversely extending weight 124.

Immediately above the weight there is mounted updh the plate a conventional mercury switch 126. Since such a switch is conventional per se, it is not deemed necessary to show the details of inner construction thereof. It is sufiicient to note that the switch is so designed that when plate 120 depends vertically in its full line position of Fig. 8, the switch will not affect the operation of the motor 20. However, the switch -is so designed and is so wired to the motor that when the plate 120 rocks from its normal, vertical position in either direction, as for example to the chain-dotted position of Fig. 8, the switch is operated to change the direction of rotation of 'the shaft 39 (see Fig. 1) by operation of the solenoidcontrolled reversing clutch 37. The switch 126 and the solenoid clutch 37 would, of course, be connected with a suitable source of electric power.

As a result, when the feeler frame engages, at either side thereof, an obstruction, the switch 126 is operated to immediately reverse the direction of rotation of shaft 39, and this in turn causes an immediate reversal of the direction of movement of the painting head so that the painting head moves away instantaneously from said ohstruction, and travels in an opposite direction even though the oscillating arm assembly has not moved through i normal full course of travel.

The manner in which the feeler frame and switch operate is shown in Fig. 8. Assuming that the feeler frame strikes an obstruction at the left of the same viewing the same as in Fig. 8 during movement of the pain-ting head toward the'left in Fig. 8, the feeler frame will be shifted to the right in Fig. 8 relativeto the tube 96. In other words, tube 96 tendsto continue its motion to the left in Fig. 8, but'the'feeler frame, having-engaged-theobstruc tion, remains stationary and hence be in the dotted 'line position of Fig. 8 relative to the tube 96. The pivotal connection of the feeler frame to the switch support rocked to its chain-dotted position of Fig. 8 by camming action of the tub 96 against the wall or edge of slot 123 during the continued movement of the tube 96 to the left in Fig. 8. As a result, the switch 126 is tilted, energizing the clutch 37 to instantaneously change the direction of rotation of shaft 39 and hence cause a corresponding, instantaneous change in the direction of movement of the tube 96 so that the painting head will move away from the obstruction. The feeler frame and plate immediately return to their normal position shown in Fig. 8 in full lines, due to the provision of the weight 124. The switch itself might constitute a suflicient weight. I

The solenoid clutch is a wholly conventional device per se and other types of clutches might be employed as well. It 'is mainly important to note that the clutch, when tripped by action of the switch 126, will operate to reverse the direction of rotation of shaft 39, while still maintaining the same in driving-driven relationship to the shaft24 extending from gear head 22.

Various means may be employed to continuously feed the coating material to the painting head. Further, the

painting head itself may be changed in construction, that shown being purely an example of a painting head that can be advantageously employed. Such changes would of course be such as will be permitted by the scope of the appended claims.

As one example for maintaining a continuous supply of paint the painting head, there is shown in Figs. 1 and 2 a paint tank or reservoir 128, equipped with a hand pump and with a capped filler neck 132. The hand pump is operated at periodic intervals to compress air within the reservoir 128 above the surface of the paint, and thereafter, paint will be forced upwardly through tube 98, which is connected with the lower end of the reservoir, into the painting head as long as sulficient pressure remains. Y

Instead of a hand pump, an electricallyoperated air compressor pump may be employed, adapted to operate that the painting head should :be maintained .with va continuous .supply of paint, to replace thaLcoated upon .the surface of the ceiling.

In Figs. 1, 2 and thereis shown themeans-for maintaining pressure within the extensible arm.assembly.6,6.

A hydraulic means is illustrated purely by way.of example, and includes a reservoir 134 mounted .upon-a ledge 136.carried 'by and extending between the side walls of housing 10. Closing thereservoinaLi-tsupper end is a removable cover .138 and-within the :reservoirthere is a supply of pressure fluid .140.

A heavy weight 142 is disposed within the reservoir 134, and extending thereabout is-a sealing ling-l44 having wiping contact with-the .side wall of the reservoir. A handle 146 on the weight itsinsertiomor removal, and in cover'138 there is an air .vent 148-10 prevent the formation of a vacuum above-the weight.

The tube 76 extending to base cylinder -'I0;is connected in communication with the lower end of rreservoir 134. Accordingly, weight 142, tending to gravitate reservoir 134, forces fluid 140 through tube 76 into base cylinder 70, to extend the shaft--elementr9otand intermediate cylinder 78. The arm assembly ithus continuously extended sufliciently to maintain thc painting roller in engagement-with ceiling C. --Whenever the :arm assembly moves across its dead centergtendingztosshonten the same, the arm assembly.is-telescopedas-previously described herein, forcing the fluid backwardlydnto .the reservoir 134 and temporarily elevating theweight 142. It be understood that the force with which the fluid is directed into the extensible arm assembly, while sufficient to maintain said assembly in anextended position, is overcome by the force with which the armrassembly .is oscillated by the means shown in Figs. 3 and 4 so that the arm assemblywill not bind and 'become stationary in any position to which it is oscillated.

:and at the same time, is traveling back and forth along disposed transversely of the direction of movement of the housing. The full lines and full line arrows in Fig. 11 show the movement of the painting roller in one direction, while the dotted lines and dotted in the same figure show the movement in the opposite direction. The painting roller in effect has azig-zag action, with its path overlapping to insure coverage of the .full

area being painted.

If obstructions are .not encountered by the. feeler frame, of course, the oscillating assembly will travel through its full angular distance between its opposite extreme positions. Should an obstruction be encountered at any point, however, the feeler frame. immediately-reverses the direction of .movement of the oscillating arm assembly in the manner previously described, so that the device continues to operate, traveling once again through itsfull distance as soon as the obstruction is In Figs. 12 and 13, there is shown a modified construction used for translating rotary motion of the drive shaft 'of the apparatus into oscillating motion of the painting arm assembly 66 shown in-Figs. 1 and 2. The showing in Figs. 12 and 13 is largely diagrammatic, inthe sense that the housing, support brackets, etc., are not shown. However, it will be understood that the mechanism il- .lustrated in these figures of the drawing will be housed in a casing such as shown at 30 in Figs. 1 andZ with the casing being mounted substantially in the same place and in the same manneras the hQusingpr-casing30.

8 Thus, thebelt 40 will be extended upwardly into the casingthroughan opening in the bottom thereof, and is ,trained aboutapulley 248. Pulley 248 issecured to and vdrives .a jackshaft 250journalled'in suitable bearings pro- ,5 vided within the housing. Shaft 250 is secured to and .drives a pulley 252 about which is trained a belt 254 passxingabout a pulley,256 secured to and driving a stub shaft .258. .Also rotating with shaft 250 is a gear 260 in mesh witha larger gear 262 secured to and driving a stub shaft 264 aligned with shaft 258. The ratio of gears 260, 262 and the ratio .of pulleys 252, 256 are identical, so that the stub shafts are turned at the same speed.

.The stub shaftsrotate the drive members of conventional solenoid clutches 266, the driven members of which rotate stubshafts 268 secured to a crank 270 to :which is pivotally connected a pitman 272. Pitman 272 is pivotally connected to a .block 274 sliding in a horizontal straight slot 276 formed in a plate 278 fixedly mounted within the housing.

.Block 274 is also pivotally connected to a pitman 280, pivotally attached to the periphery of a gear 282 secured 10a stub shaft 284, that is in turn fixedly secured to the lower end of the tubular member 70 of thearm assembly 66.

In mesh with gear 282 is a counterbalancing gear wheel 286 having a weight 288 secured thereto. The weight is so arranged as to provide a balance for the painting arm assembly, at Opposite extreme limits of the travel of .said assembly during its oscillation in the path previously describedherein.

The arrangement is one in which there is continuous rotation of the crank 270. This causes the pitman 272 to impart reciprocating motion to the block 274. In turn, the reciprocation of the block causes rotation of gear 282 through a predetermined number of degrees in one direction, with this movement being followed by reverse ro tation of the gear wheel 282 in the opposite direction; in other words, when block 274 travels toward one end of the slot the gear wheel rotates in one direction. When 40 the block travels :toward the opposite end of the slot the gear wheel will turn in an opposite direction. The number of degrees of angular distance that the gear wheel turns is,-of course, within the option of the manufacturer and will depend upon the extent to which the paint arm assembly 66 is to swing between its opposite extreme positions.

The counterbalance .means 286, 288 is alsoan optional feature and may in some instances be eliminated if desired.

It will be understood that the solenoid clutches are controlled by the electrical switching means provided upon the painting head. The clutches are of a type such that when the solenoids thereof are energized, the clutches willdrive the stub shafts in one direction. When the solenoids are .deenergized, the clutches reverse the direction of rotation of the stub shaft 268.

Thus, there .is continuous unidirectional movement of stub shafts 258, 264, and there is also a constant drivingdriven relationship between these stub shafts and the stub shafts 268. There is, however, an arrangement such that whenever the switches on the painting arm are tripped by striking an obstruction, the solenoid clutches will be operated to reverse whatever direction the stub shafts 268 are turning in at the particular moment. Of course, if the switches do not strike an obstruction, the reversal of direction of the painting arm assembly occurs at the normal limits of its travel, without change in the direction of rotation of the stub shafts 268.

While -I have illustrated and described the preferred embodiments of my invention, it is to be understood that I do not limit myself to the precise constructions herein disclosed and thatv various changes and modifications'may be made within the scope of'the invention as defined in the appended claims.

Having thus described my inventiomwhat I cIaimJas wheeled support, self-propulsion means therefor, painting head support means carried by said support, a painting head carried by the painting head support means, said painting head support means and painting head being operatively arranged to cause reciprocating movement of the painting head over a surface to be painted during selfpropelled movement ofthe wheeled support, means to feed paint to the painting head, and means on the painting head for reversing thedircctionof movement of the head on engagement of the direction-reversing means against an obstruction disposed in the path of the painting head, the self-propulsion means comprising a motor mounted within the support, a reducing gear head on the motor, and driving connections between the gear head and the wheels of the support, the painting head support means including an arm oscillatingly supported upon the wheeled support and projecting upwardly therefrom, the painting head being mounted upon the upper end of the arm for painting a ceiling surface on oscillation of the arm.

2. An automatic painting machine comprising a wheeled support, self-propulsion means therefor, painting head support means carried by said support, a painting head carried by the painting head support means, said painting head support means and painting head being operatively arranged to cause reciprocating movement of the painting head over a surface to be painted during self-propelled movement of the wheeled support, means to feed paint to the painting head, and means on the painting head for reversing the direction of movement of the head on engagement of the direction-reversing means against'an obstruction disposed in the path of the painting head, the self-propulsion means comprising a motor mounted within the support, a reducing gear head on the motor, and driving connections between the gear head and the wheels of the support, the painting head support means including an arm oscillatingly supported upon the wheeled support and projecting upwardly therefrom, the painting head being mounted upon the upper end of the arm for painting a ceiling surface on oscillation of the arm, said machine including a motiontranslating linkage between the motor and the arm adapted to effect oscillating movement of the arm responsive to operation of the motor, to produce said reciprocating movements of the painting head.

3. An automatic painting machine comprising a wheeled support, self-propulsion means therefor, painting head support means carried by said support, a painting head carried by the painting head support means, said painting head support means and painting head being operatively arranged to cause reciprocating movement of the painting head over a surface to be painted during self-propelled movement of the wheeled support, means to feed paint to the painting head, and means on the painting head for reversing the direction of movement of the head on engagement of the direction-reversing means against an obstruction disposed in the path of the painting head, the self-propulsion means comprising a motor mounted within the support, a reducing gear head on the motor, and driving connections between the gear head and the wheels of the support, the painting head support means including an arm oscillatingly support upon the wheeled support and projecting upwardly therefrom, the painting head being mounted upon the upper end of the arm for painting a ceiling surface on oscillation of the arm, said machine including a motion-translating linkage between the motor and the arm adapted to effect oscillating movement of the arm responsive to operation of the motor, to produce said reciprocating movements of the painting head, said arm being of telescopic formation so as to maintain the painting head in engagement with the surface 'being painted during oscillating movement of the 4. An automatic painting machine comprising a wheeled support, self-propulsion means therefor, painting head support means carried by said support, a painting head carried "by the painting head support means, said painting head support means and painting head being operatively arranged to cause reciprocating movement of the painting head over a surface to be painted during selfpropelled movement of the wheeled supporhmeans to feed paint to the painting head, and means on the painting head for reversing the direction of movement of the head on engagement of the direction-reversing means against an obstruction disposed in the path of the painting head, the self-propulsion means comprising a motor mounted within the support, a reducing gear head on the motor, and driving connections between the gear head and the wheels of the support, the painting head support means including an arm oscillatingly supported upon the wheeled support and projecting upwardly therefrom, the painting head being mounted upon the upper end of the arm for painting a ceiling surface on oscillation of the arm, said machine including a motion-translating linkage between the motor and the arm adapted to effect oscillating movement of the arm responsive to operation of the motor, to produce said reciprocating movements of the painting head, said arm being of telescopic formation so as to maintain the painting head in engagement with the surface being painted during oscillating movement of the arm, the machine including a means to supply fluid under pressure to the arm, the arm comprising a plurality of telescopically related sections responding to the fluid pressure to extend the arm.

5. An automatic painting machine comprising a wheeled support, self-propulsion means therefor, painting head support means carried -by said support, a painting head carried by the painting head support means, said painting head support means and painting head being operatively arranged to cause reciprocating movement of the painting head over a surface to be painted during self-propelled movement of the wheeled support, means to feed paint to the painting head, and means on the painting head for reversing the direction of movement of the head on engagement of the direction-reversing means against an obstruction disposed in the path of the painting head, the self-propulsion means comprising a motor mounted within the support, a reducing gear head on the motor, and driving connections between the gear head and the wheels of the support, the painting head support means including an arm oscillatingly supported upon the wheeled support and projecting upwardly therefrom, the painting head being mounted upon the upper end of the arm 'for painting a ceiling surface on oscillation of the arm, said machine including a motiontranslating linkage between the motor and the arm adapted to eflect oscillating movement of the arm responsive to operation of the motor, to produce said reciprocating movements of the painting head, said arm being of telescopic formation so as to maintain the painting head in engagement with the surface being painted during oscillating movement of the arm, the machine including a means to supply fluid under pressure to the arm, the arm comprising a plurality of telescopically related sections responding to the fluid pressure to extend the arm, said last-named means including a tank mounted in the wheeled support, a supply of pressure fluid within the tank, a weighted, floating piston within the tank exerting a downward pressure on the supply of pressure fluid, and a flexible, tubular connection between the tank and said arm.

6. An automatic painting machine comprising a wheeled support, self-propulsion means therefor, painting head support means carried by said support, a painting head carried by the painting head support means, said painting head support means and painting head being operatively arranged to cause reciprocating movement of the painting head over a surface to be painted during self- :propelledmovement of the wheeled supp0rt,-means to feed paint to therpainting head, and means onthe painting'head for reversing the direction of movement of the head on engagement of the direction-reversing means switch deviceoperated by said feeler-frameon engagement of the-'feeler frame against said obstruction and arrangedfiooperatethepaintinghead in a reversetdi- 'rcction, saidgswitch device comprisinga switch plate 12 rockably carried by the painting head support means the frame-beingpivotally connected to said switch plate to rock the same responsive to engagement of the frame against said obstruction, and a mercury switch carried by the switch plate in position to be tilted responsive to rocking ofthe switch plate.

References Cited in the file of this patent UNITED STATES PATENTS 208,366 Brooks Sept. 24, 1878 2,190,576 Sisman Feb. 13, 1940 2,559,295 Grossenbacher July 3, 1951 

